Many pundits felt Arsenal might have been kissing goodbye to their top-four hopes by letting two of their star men leave for a major rival.

Yet the early signs do not indicate there will be a problem.

The Gunners have scored 10 goals in their first two matches, including six at Everton on the opening day, and also reached the group stages of the Champions League by putting five past Celtic.

And Ferguson, whose Manchester United tackle Arsenal in the first blockbuster confrontation of the Premier League campaign at Old Trafford this evening, is adamant Wenger knows exactly what he is doing.

“I couldn’t understand why they were written off,” said the United boss.

“A young team like Arsenal, that is maturing, has to be respected and regarded. Six-one at Everton was an amazing result. In all my time at Manchester United, I can’t remember anyone doing that at Goodison Park before.

“But one thing Arsene Wenger has done fantastically well is sell at the right time.

“He has always known the right time for a player to leave and he has done it again with Adebayor and Toure.

“It is not easy to manage that kind of change but I don’t think the level of ability has changed one bit and he seems to have a good harmony in the squad.”

There was a point when United games against Arsenal needed to be viewed from behind a sofa.

“Over the years Manchester United games against Arsenal have been the feature of the Premier League,” said Ferguson.

“For a long time we were both competing for the number one spot and some of the games were very feisty.

“The character of the teams has changed a bit. We don’t have a Keane, they don’t have a Vieira. They were both volatile characters and dominant figures in their teams.

“Tomorrow won’t be in any way as competitive. It will be a different type of game.”

Ferguson must decide whether to make changes, knowing Michael Carrick and Anderson will be desperate to make an impact after missing last week’s five-goal rout of Wigan.

In addition, both Dimitar Berbatov and Michael Owen got their names on the scoresheet for the first time this season, although both trail Wayne Rooney by three after the England man’s double took his United tally to 101.

Although United have now found their feet after a tricky opening week, that shock defeat at Burnley has left them trailing three clubs, including Arsenal, who still have 100% records.

So, while Ferguson is not convinced much can be gleaned from one battle, he does not want United to drop any more points, particularly given his team struggled against all the big four last season, and managed to register just one win in six outings.